In the supervisory control of industrial plants there is significant need for information about equipment, current and historic process data, trends, etc. This information is typically provided by the control system and usually in the form of one or more distributed control systems (DCS) and/or supervisory control and data acquisition (SCADA) systems. With the increases in computing power and advances in communication and computerized measurement there is an increasing amount of data available for the operators.
The information is today often presented to the operators through display screens showing process graphics that presents process data (measurements, values), tag identifiers, equipment id, alarm status, connections between plant equipment, etc. As more and more data is being presented to the operators, the visual user interfaces often hold very much information. It can be difficult for the operator to determine what is important information and what is not. One reason for this cluttered look in the process graphics in some cases may not the actual amount of information presented, but rather poor design with for example an unnecessary prominence of static information presented with thick lines and strong colours, which make it difficult for an operator to use such displays as a technical tool for efficient search, retrieval and evaluation of information stored in one or more databases. The problem of finding the relevant technical information in a large information space is further complicated by the fact that in many situations the operator often has limited time available to make a decision. The significance of the information available will vary with the current situation. That is, users of industrial control systems have to deal at least in part with a context sensitivity problem, as in some context certain information will be essential and in others irrelevant.
WO02084596 entitled Simultaneous display of data and/or objects in layers on a display screen, describes a system and method for displaying objects in a plurality of layers on a visual display. The layers are distinguished from one another using a variety of display attributes in order to emphasize objects in upper layers and de-emphasize objects in lower layers. The user is able to change the layering in order to emphasize a different group, or category, of objects and de-emphasize other groups. The layers can be predefined, for example hardware and software layers, or may be defined by analyzing the attributes corresponding with the objects. Objects and their attributes are stored in a data store, such as a relational database. Predefined layers include one or more of these attributes to use for matching.
WO2005109124 entitled A process plant user interface system having customized process graphic display layers in an integrated environment, assigned to IBM, describes a method useful for providing a user interface for a process plant. It includes displaying graphical depictions of process plant elements of the process plant via the user interface. Information is generated for a plurality of content layers of a process graphic display of the process plant elements by processing data regarding operation of the process plant. Content to be displayed via the user interface is determined from the generated information by determining which content layer of the plurality of content layer is to be displayed. In some embodiments, the determination may be made based on a user profile characteristic. The generated information may therefore support multiple views of the process plant via the user interface for a plurality of different types of users of the user interface, and may involve processing data regarding actual and simulated operation of the process plant.
Some control systems also have a concept called layers or filters. These layers are used in the engineering of the system, to separate what information should be shown to which type of users when the system is being engineered. For example this can be used for hiding information that is only relevant to IT support personnel from process engineers or the operators.